Technical Field
The present invention relates to a roller hemming processing apparatus and a roller hemming processing method, to conduct a hemming coupling on a panel-like workpiece.
Related Art
This type of roller hemming processing system has been proposed by the present applicant, as discussed in Patent Document 1. The roller hemming processing system as discussed in Patent Document 1 is adapted so as to provide a plurality of claw portions around a hemming die. At the time of loading a panel-like workpiece (previously formed with a hemming flange portion) on the hemming die, these claw portions contribute to the positioning of the workpiece. Then a roller hemming processing tool (for example, held by a robot arm) is moved along the longitudinal direction of the hemming flange portion while being pressed against the hemming flange portion, thereby achieving a preliminary bending (a pre-hemming processing) or a main bending (a main-hemming processing).
In such a roller hemming processing, the claw portions that govern the positioning of the workpiece sometimes interfere with the hemming processing tool in accordance with a shape of the hemming processing tool and the like. Depending on the extent of the interference, there may arise a fear that a hemming process quality is adversely affected. In the roller hemming processing system as discussed in Patent Document 1, therefore, it is necessary to move the hemming processing tool along such a locus as not to interfere with the claw portions around portions of the hemming flange portion corresponding to the positioning claw portions. However, the thus controlled locus of the hemming processing tool becomes complicated. In addition, it is also necessary to reduce the moving speed in the vicinity of the portions in question, which is not preferable because the productivity should inevitably be lowered.